Method of and device fob starting



Dec. 24, 1935. ROE 2,025,074

METHOD OF AND DEVICE FOR STARTING COMBUSTION IN OIL BURNERS Filed Oct. 14,. 1953 $4 ATTORNEY Patented Dec. 24, 1935 UNITED STATES METHOD or AND DEVICE son sraa'rmo COMBUSTION m on. commas Nathaniel Roe, Patchogue, N. Y.

Application October 14, 1933, Serial No. 693,550

23 Claims.

My invention relates to improvements in methods of and means for igniting or starting the combustion of the fuel in oil burners or the like, and the same has for its object to provide a simple, efficient and reliable device which operates electrically to start the combustion, and which is produced at low cost and readily installed to effectively operate without being detrimentally affected by the heat of combustion during normal operation of the burner.

Further, said invention has for its object to provide a device of the character specified which is particularly adapted for starting the combustion of mixtures formed during normal operation by carburetion of the air by surface contact with a layer of fuel oil or by surface vaporization thereof.

Further, said invention has for its object to provide a device of the character specified in which the igniting or vaporizing element thereof is rendered incandescent for igniting the mix-' ture in starting or restarting the combustion.

Further, said invention has for its object to provide a device of the character specified in which the incandescent element thereof functions both to vaporize the fuel to form a combustible mixture and to cause ignition of the mixture thus formed.

Further, said invention has for its object to provide a device of the character specified in which the igniting means thereof operates to ignite a combustible mixture within a localized area under confinement to facilitate such ignition.

Further, said invention has for its object to provide a device of the character specified which is fully protected from the heat produced during normal combustion.

Further, said invention has for its object to provide a device of the character specified in which means is included for the passage of air in contact with the confined heating element to facilitate the vaporization of fuel and form a combustible mixture.

Further, said invention has for its object to provide a device of the character specified in which means is included for causing a forced draft of air through and about the heating element enclosure or housing.

Further, said invention has for its object to proprovide a device of the character specified in which the heating element thereof during the normal combustion is confined substantially entirely within the zone of unconsumed gases beiwelen the flame and the surface of the vaporizing Further, said invention has for its object to provide a novel method of starting combustion or forming and igniting a combustible mixture.

Other objects will in part be obvious, and in 10 part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends, my invention consists in the novel features of construction, and in the combination, connection and arrangement of parts, and in the several steps constituting my method, hereinafter more fully described and then pointed out in the claims.

In the accompanying drawing:

Figure 1 is an elevation, with parts broken away and parts in section, of an oil burner having applied thereto one form of device construct- :id according to and embodying my said inven-,

Fig. 2 is an enlarged sectional elevation of the device;

Fig. 3 is a similar sectional elevation of a modifled form of device; and

Fig. 4 is a similar sectional elevation of a further modification of the device.

This application is a continuation-in-part of my copending application Serial No. 676,653, filed June 20, 1933.

In Fig. 1 is illustrated one type of oil burner Hi to which the combustion starting means ll embodying my invention may be applied. The burner includes a burner unit l2 operatively associated with a motor driven blower unit l3 including the usual means It for automatically controlling, as by the usual room thermostat, the 40 operation of the motor and flow of fuel to the burner unit l2, as more fuly disclosed in said application Serial No. 676,653.

The burner unit l2 comprises a casing I! open at the top and having communication with the blower 13 through a pipe It.

A retort [1, open at the top, is receivedwithin and closes the top of the casing l5, being supported by a flange 18 from the upper edge of the casing IS in spaced relation to the lateral and bottom walls thereof. The retort I1 is provided with a central annular air inlet l9 extending upwardly from the bottom 20 of the retort. The fuel oil for combustion flows by g avity through pipe 2| from the main supply into the annular space H! within the retort ll to form a shallow layer on the bottom 23 thereof. and provides an extended surface for fuel vaporization, the depth of the fuel in the retort l'| being limited by operation of the float 22. 4

A hollow air distributing member 23 is supported upon and communicates with the air inlet and projects upwardly well beyond the upper edge of the retort H. The member 23 within the conilnes'of the" retort, is provided with an enlarged portion 24 overlapping the upper edge of the air inlet l9, which portion contains holes 25 for discharging air in jets outwardly and downwardly intothe retort l1, and towards the surface of the fuel therein, the air escaping over the top edges of the retort H. The member 23 at the upper end is provided with a mushroom portion 24 having a slot 21 therein through which air'is discharged laterally outwardly in all directions to spread out the flame. Combustion is also supported by discharge of air in Jets from the interior of the casing l through a series of holes 23 provided in the flange 13 contiguous to and about the discharge end of the retort I'I.

During normal operation of the burner air is forced by the blower into the retort ll through the holes 25, about the retort through holes 23, and through the marginal slot 21. The heat of combustion, assisted by the air jet action on the surface of the fuel is then suflicient to cause fuel vaporization and admixture of the vaporized fuel with the air introduced. The flame or combustion occurs at the mouth of the retort, the air mixing with the fuel prior to combustion in accordance with the Bunsen principle so that during normal operation the space I! contains unconsumed combustible mixtureand is at a relatively lower temperature, the temperature reducmatic valvular means 29 for controlling the fuel flow. The electrical control I4 is preferably operated by a thermostat adapted to close the fuel passage when the temperature exceeds a predetermined value, and to also open the fan motor circuit when the fuel in retort I1 is exhausted. As the temperature decreases the reverse operation occurs, all as more fully disclosed in my said copending application Serial No. 676,653.

with the burner apparatus of the type herein described constantly burning gas or oil pilots are employed for heating up the fuel oil and causing the ignition of the resulting mixture each time oil is admitted to the retort IT by operation of the thermostat, or upon initial starting of the burner.

In the present invention I dispense with the use of gas or oil pilots and provide electrical means ll producing heat for initiating the combustion which means is very efiective in starting the combustion of high boiling point non-volatile fuels and which is capable of being energized only when needed, and preferably automatically controlled by means 3| under the control of the' usual room thermostat to be operated temporarily upon the initiation of each combustion v the conductor 43, such as an iron wire, the end portion 44 of a heating coil 45, preferably of nichrome" wire or other high resistance wire being wound about the portion 42 of conductor 43, and the parts soldered together at the ends to provide a portion 45' engaging the outer end of the member 33 to prevent withdrawal of the parts from the hole 40. The member 33 is retained in position by a plug 45 threaded into the end 33, suitable insulation 41, such as asbestos or the like, being disposed between the plug 45 and the anchoring portion 45'.

The wire 43 from the porcelain 33 curves outwardly through the extension 35 and is maintained centered in spaced relation to the walls of the housing 32 by passing through an open ended metal tube 43 received within the central opening 49 in a split plug 50 threaded into the open end 36 of the extension 35 and serving, when in place, to exert a clamping action on the tube 43 to retain the tube in place. The wire 43 is also additionally insulated by stringing insulating beads 5| thereon, the beads being retained thereon by forming a loop 52 at the end of the wire 43; The opposite end 53 of the heating coil 45 is preferably secured and grounded to the housing 32 at a point 54 contiguous to the open end 34 of the housing in such relation as to keep the body of the coil 45 in spaced relation to the walls of the housing 32.

As shown in Fig. l, the member 32 is disposed within the space Il at the side thereof remote from the point of introduction of fuel and rests at an inclination upon the floor 20 so that the opening 34 faces toward the air inlet i9 and provides an. air opening or'inlet above the surface of the fuel. The member 32 is supported in inclined position by the tube 43 extending through the wall of the air distributor 23 and communicating with the interior thereof so that the air passage serves as a protective conduit for the lead or leads to the control mechanism from the igniting device.

The housing 32 is preferably provided with a diagonal cut or chamfer at the lower end thereof at one side as indicated at 55, to form supporting edges 55 lying in a plane substantially intersecting the lower turn or turns of the coil 45 and providing a firmer engagement with the bottom 20, and an intervening tapered opening 51 exposing the fuel to heating action of the coil 45, the lower end of the coil 45 being submerged in the fuel and yieldably bearing on the bottom 20 of the retort H. The member 32 is also provided with a longitudinal slot 53 through the opposite side thereof exposing substantially the entire heating coil 45 and merging at the lower end thereof with the tapered end of the submerged chamfered opening 51.

The device as above constructed, when secured in the inclined position shown at Fig. l, insures entrance of air into the interior of the device II at the lower end thereof through the substantially semi-circular opening 34; the air on entering the device being forced to pass over a localized portion of the surface of the fuel, where the same is being heated by the submerged portions of the heating .coil .and upwardly over the entire exposed portion of the coil, the air passing out through the elongated slot 58 towards the rim of the retort II. The travel of air is biased to travel in the direction described because of the forced draft.

The resistance of the heating coil and the current passing through the same are relatively adjusted to produce heat sufficient to eflect rapid vaporization of the fuel to produce a combustible mixture, and to heat the mixture to the flashing point; the vaporization being facilitated by the effect of the moving air. The air in or entering the housing 32 readily becoming permeated with being automatically cut out of circuit.

By my method, although employing a comparatively small heating coil 45, I am able to readily vaporize a non-volatile fuel having a high boiling point, such as fuel oil and the like, within a localized area to form a combustible mixture within the confined space which quickly reaches the flashing temperature and ignites. This is preferably eifected by submerging one or more of the lowermost turns of the heating coil directly in the oil at a point below the air confining point to heat the oil, and thereby augmenting the external surface vaporizing effect of the incandescent exposed portion of the coil 45 which is utilized to heat the combustible mixture formed within the confines oi the housing 32 to the flashing point. If so desired, said housing 32 may be composed of a porous refractory material capable of absorbing oil to render the oil more readily ignitable.

In Fig. 3 I have illustrated a modification of the igniting means H which comprises a tubular housing 60 open at one end 6| and closed at the other end 62 by a screw plug 63 which is removable to allow inspection of the interior of the device. A heating coil or element 64 is loosely disposed within the housing and is supported by the terminals or leads 65 thereof, passing out through a tubular outlet 66 in the side of the housing, which outlet 66 is adapted to be secured in and to communicate with the air distributing member 23 serving as a protection conduit for the leads. The member 60 is supported at an inclination in the retort IT in the manner above described with the mouth 6| thereof at the bottom forming an air inlet immediately above the fuel for the passage of air into the housing 60 at the lower end thereof in close contact with the localized area of the fuel surface below the outlines of the lower end 6| of the housing, the air passing out through a longitudinal slot 61 at the opposite side of the housing 60 after contacting with the incandescent coil 64. In this form of the device the entire coil 64 is exposed to the air or combustible mixture and is relied on without submergence of a portion thereof for effecting fuel vaporization and for. heating the resulting partially confined combustible mixture to the flashing point.

In the modification shown in Fig. 4 the igniting means comprises a housing 68 closed at one end 69 and open at the other end 10. The housing is also provided with a lateral opening ll therein receiving a block or plate I2 of refractory material carrying terminal connection elements 13. A coil or heating element I4 is disposed within the housing 88. and is secured at the ends thereof to the inner ends of said terminals II to be firmly supported thereby in spaced relation to the walls of the housing. The block 12 carries a tubular conduit through which the lead wires 16 pass to be secured to the outer ends of the terminals 13. The block or plate 12 may be removed as a unit with the coil 14 through the lateral opening H and is retained in position by clips 11.

The housing 88 is mounted at an inclination supported by the tube 15 on the air distributor 23 as in the other forms described with the open end 10 thereof extending above the fuel surface to provide an air inlet to the interior of the device. When the coil 14 becomes incandescent the heat vaporizes the fuel, and the resulting mixture then ignites in the confined space within the housing 68. In this form of device the longitudinal air outlet slot is omitted so that the mixture is ignited while being confined to the maximum extent.

The device embodying my invention is simple in construction, durable, and efficient in operation from the standpoint of expense, effectiveness and safety. The device may be employed without interfering with the normal operation of the burner, occupying a minimum of space within the vaporizing retort I1, and is readily controlled so that it only operates to consume current during the starting stage of combustion.

By my invention I am able to substantially instantaneously heatup a localized portion of a layer of fuel oil in a surface carburetion type of burner to form a combustible mixture within a confined or partially confined space which quickly ignites, the resulting flame or the heat thereof being propagated over the surface of the fuel to accumulatively increase the general vaporizing effect and heat until normal combustion is attained.

Having thus described my invention what I claim and desireto secure by Letters Patent is:

l. The herein described method of starting combustion which consists in concentrating by confinement the heat from an incandescent body upon a localized portion of a layer of fuel oil and thereby vaporizing the same and igniting the resulting mixture received within the confined space by the action of heat from said incandescent body and causing the resulting flame to be propagated from within said confined space over contiguous portions of said liquid fuel layer.

2. The herein described method of starting combustion which consists in vaporizing a localized portion of a layer of fuel oil and igniting the resulting mixture while under confinement by the action of an electrical current and resulting heat generated within the confined space and concentrated thereby upon said localized fuel portion, and venting the resulting flame from within said confined space over the contiguous portions of the liquid fuel layer.

3. The herein described method of starting combustion which consists in. passing an electric current through a body to cause an emission of heat from said body, and confining said heat within an enclosure having the interior thereof in exposed relation to a localized portion of a layer of fuel oil for causing vaporization of the fuel and the'confinement of the resulting combustible mixture within said enclosure subject to the action of said heat for causing ignition of the mixture-and venting the resulting flame from within said enclosure over the contiguous portions of the liquid fuel layer.

"5 4. The hereindescribed method of starting combustion which consists in subjecting a localized portion of a layer of fuel oil to the heating effect of an electrically heated body in part submerged in the fuel and in part disposed above said localized portion and confined to concentrate the heat upon the surface of said localized fuel portion, and effecting thereby'fuel vaporization and ignition of the resulting combustible mixture within the confined space, and causing the flame to be propagated from within said space over the contiguous portions of the liquid fuel layer.

5. The herein described method of starting combustion which consists in subjecting a 10- v calized portion of alayer of fuel oil below a partially confined space to the action of a body disposed within said'space and extending into the fuel layer and traversed by an electric current and emitting heat, and causing passage of air into said confined space at a point contiguous to the surface of said localized portion of fuel oil and over said heat emitting body for effecting fuel vaporization and ignition of'the combustible mixture formed within said confined space, and

a0 propagation of the flame therefrom over the contiguous portions of the liquid fuel layer.

6. The herein described method of starting combustion which consists in subjecting a loca ized portion of a layer of fuel oil to the action 3.5 of a body heated by the action of an electric current, and in part submerged in said fuel and in part exposed to the air under confinement and causing air to pass through said confined space in contact with the surface of said localized por- 40 tion of fuel, whereby tocause ignition of the combustible mixture formed within said confined space, and to facilitate propagation of the flame over the contiguous portions of the liquid fuel layer for starting normal combustion.

15 7. The herein described method of starting combustion which consists in causing a forced draft of air over a layer of fuel oil for'normally supporting the combustion of said fuel oil, and subjecting a localized portion of the layer of fuel 50 oil to the action of a heat emitting body disposed thereover under confinement while causing fiow of air under the action of said draft into the confined space at a point contiguous to the surface of the fuel, and over said heat emitting body 55 for discharge from said space at the opposite side. a

8. The herein described method of starting combustion which consists in generating heat electrically and concentrating the same by con- 60 finement upon a localized portion of a layer of fuel oil, receiving the vapor thus generated within the confined space, igniting the mixture by the heat generated, and causing the flame to be propagated therefrom over contiguous portions 65 of said fuel layer.

\ 9. The herein described method of starting combustion which consists in generating heat electrically and concentrating the same by confinement upon a localized portion of a layer of 70 fuel oil, receiving the vapor thus formed within the confined space, igniting the mixture therein by the heat generated, and venting the inflammation therefrom contiguous to said fuel layer to cause flame propagation thereover.

75 10. In a device of the character described, a

retort for holding a layer of fueloil, a housing within saidretorthavinganopeningatthelower end thereof disposed to exposethe'interlor of the housing to a localized'portionof a layer of fuel oil and provide a passage above the fuel level 5 into said interior, and an electrically conductive heating element within said housing.

11. In a device of the character described, a retort for holding a layer of fuel oil. a housing within said retorthaving an opening at thelower 10 end thereof disposed to exposethe interior of the housing to a localized portion of a layer of fuel oil, said opening including an inlet and an outlet for the passage of air, and an electrically conductive heating element within said housing. is

13. In a device of the character described, a 25 housing having an opening at the lower end thereof, said housing at said opening having a diagonal chamfer providing supporting edges therefor at opposite sides of a portion of said opening, said opening beyond said chamfer proso viding a lateral air inlet to the interior of the housing, and an electrically conductive heating element disposed within said housing.

14. In a device of the character described, a housing having an opening at the lower end thereof and including supporting edge portions at opposite sides of said opening, and a heating element in said housing terminating at the lower end thereof in the plane of said supporting edges.

15. In a device of the character described, a housing having an opening at one end thereof including a chamfer providing supporting edgesat opposite sides of a portion of said opening, and an electrically conductive heating coil disposed within said housing and extending below said supporting edges to yieldably engage the surface supporting the device.

16. The combination with an oil burner including a vaporizing retort adapted to contain'a layer of fuel oil, of a housing disposed in said retort and having-an opening at the lower end thereof in exposed relation to a localized portionof the layer of fuel oil, and an electrically conductive heating element in said housing. 17. The combination with an oil burner'including a vaporizing retort adapted to contain a layer .of fuel oil, of a housing having an opening at the lower end thereof and supported upon the bottom of said retort at an inclination to expose a localized portion of the layer of fuel oil to the interior of the housing,'said opening in part extending above the fuel level to provide a passage into the housing, and a heating element in said housing.

18. The combination with an oil burner inas cluding a vaporizing retort adapted to contain a layer of fuel oil and means disposed centrally of said retort for introducing airunder forced draft into the burner for supporting the combustion, of a housing supported upon the bottom of said retort and having an opening at the lower end thereof exposing the interior of the housing to a localized portion of the fuel oil and providing an air inlet above the fuel level, an electrically conductive heating element in said housing and a laterally extending conduit on said housing communicating with said air introducing means and receiving the lead or leads from said heating element.

19. If a device of the character described, a housing having an opening at the lower end thereof disposed substantially in exposed relation to a localized portion of a layer of fuel oil, and having the axis thereof at an inclination, the lower end of said housing being partially submerged within said layer of fuel oil, and said opening extending above the fuel level to provide a vent into said housing between the lower end thereof and said fuel layer, and an electrical heating element disposed within said housing.

20. In a device of the character described, a housing having an opening at the lower end thereof disposed substantially in exposed relation to a localized portion of a layer of fuel oil, and having the axis thereof at an inclination to said fuel oil layer to provide a vent into said casing above the fuel level through the lower end of said housing at one side thereof, said housing having a lateral opening therein at the opposite side, and a heating element in said housing.

21. The combination of an oil burner including a vaporizing retort adapted to contain a layer of fuel oil, with a housing disposed within said retort below the upper edge thereof, and having an opening at the lower end thereof overlying a localized portion of the fuel layer, and an electrical element within said housing for generating the heat to be concentrated on said localized area by said housing; said housing serving to receive the resulting combustible mixture for ignition and being vented into the retort space above the fuel level.

22. The combination of an oil burner including a vaporizing retort adapted to contain a layer of fuel oil, with a housing open at the lower end and disposed within said retort upon the bottom thereof, and at an inclination thereto to provide a vent into said housing through said opening between the fuel layer and the lower end of the housing, and a heating element within said housing.

23. The combination of an oil burner including a vaporizing retort adapted to contain a layer of fuel oil, and means for introducing air into said retort under forced draft, with a housing open at the lower end disposed within said retort upon the bottom thereof and at an inclination thereto, said opening extending above the fuel level to provide a vent, an electrical heating elementwithin said housing, and a lead conduit extending laterally from said housing, communicating with said air introducing means and serving to retain said housing in inclined position.

NATHANIEL ROE. 

